This invention relates to an overflow preventer primarily but not exclusively for baths and sinks.
Baths and sinks may be provided with overflows which direct excess water to a drain. The overflow may however not be able to cope with the flow of water and spillage may still occur.
GB 2 261 600 (Lewis) describes an overflow preventer in which passage of water through a conduit attached to the overflow causes the plug to be displaced from the overflow. The arrangement is very expensive to make and fit. Furthermore when the preventer is actuated its action is irreversible. This means that if a bath is filled rather full and a bather displaces water so that some passes through the overflow the device will be actuated and unless reset all the water will drain from the bath leaving the bather high and dry.
According to some embodiments of the invention there is provided an overflow preventer comprising a plug receivable in a drain hole and provided with a valve movable between a first closed position and a second open position, the valve being resiliently biased to the first position while the pressure on the valve is less than a predetermined value.
The valve may be resiliently biased for example by a spring such as a compression spring or a tension spring.
The valve may be a annular valve. A circumferential valve seat may be provided in the plug. The valve may be provided with an O-ring for sealing on the seat of the valve body. The plug may comprise resilient plastics material. The outer circumference may be provided with an O-ring to engage sealingly with the plug hole.